Quick Q: Does std::vector resize automatically when inserting new elements?--StackOverflow

By Jared Mulconry | Nov 28, 2014 09:54 AM | Tags: basics

Quick A: Yes.

Recently on SO:

Do Vectors resize automatically?

I am very sorry that I am asking such a beginner question but I am finding contradictory information online. I would ask at University but it is out until February next year.

Do Vectors resize automatically? Or do you need to check the current size periodically and resize when you need more room. It looks to be resizing for me automatically but I'm not sure if that is a feature or the compiler waving a magic wand.

Poco C++ Library release version 1.4.7p1

By Felix Petriconi | Nov 28, 2014 09:53 AM | Tags: None

POCO Development Release 1.4.7p1 Available

This release fixes a few issues in 1.4.7 and earlier releases. Most important, the Visual C++ project files for Visual C++ 2010 and later have optimization enabled in release builds. Previous builds had optimization disabled due to a bug in Visual Studio when upgrading 2008 project files with custom optimization settings.

There’s a new feature as well – HTTPClientSession now supports a global proxy setting, which will be used by all instances of HTTP(S)ClientSession, including HTTP(S)StreamOpener.

Detailed information is available in the CHANGELOG.

Anti-IF idioms in C++ -- Marco Arena

By Marco Arena | Nov 28, 2014 09:46 AM | Tags: intermediate community c++14 c++11

I'm showing interactive examples of "anti-IF" idioms in C++, inspired by C# snippets which Claudio Pattarello proposed at the Italian Agile Day 2014.

Anti-IF idioms in C++

by Marco Arena

From the article:

In this post I’d like to show you how to rewrite these idioms in C++, starting from a C# snippet. And the resulting code is pretty much identical. [...] I'm not saying "this is the best thing you can do in C++". [...] Sure, we have specific idioms in our favorite language but I think it’s lovely that we are able to reuse the same code from other languages with a little effort. And this is also appealing for other programmers who want to experience C++, maybe by starting coding idioms they know. ...

Metaprogramming with Modern C++: The Haskell Metaphor -- Manu Sánchez

By Jordi Mon Companys | Nov 28, 2014 09:35 AM | Tags: None

If you are one of who have been following our post series about template metaprogramming with modern C++, at this time you should have become a C++ template Guru. At least thats what I expect .

You know about class templates, function templates, value parameters, type parameters, variadic templates… Your template metaprogramming toolbox is full of great things to play with. Thats good, but you want to start playing with your compiler, writting some cool metaprograms.

Metaprogramming with Modern C++: The Haskell Metaphor

by Manu Sánchez

From the article:

Template metaprogramming was used to improve perfomance on high-computing libraries too, with some clever code transformations done thanks to tmp. The best example of this is the blitz++ library, one of the first examples of a real use case of template metaprogramming.

Since C++11 the language has evolved to support some ways of metaprogramming as a common and useful thing. Metaprogramming became a first class citizen in C++, instead of the obscure, magical, and freaking way to abuse the compiler it was at the beginning...

A software design principle: Don’t make me use your design -- Diego Rodríguez-Losada

By Jordi Mon Companys | Nov 28, 2014 09:32 AM | Tags: None

Developing code in C++ for robotics, I often faced the problem of communicating via serial port with a robot, a sensor or any other device. C and C++ are languages supposedly very close to hardware. Furthermore, they are the most common and oldest mainstream programming languages out there. So communicating over a serial port in a portable way should be straightforward.

A software design principle: Don’t make me use your design

by Diego Rodríguez-Losada

From the article:

I have seen the pattern described in the article a few times in C and C++ projects, but very rarely in other languages (at least those that I have used more as java and python) and I believe there is a reason, not directly related to software design for it: the lack of a widely used dependency manager. And no, OS package managers, installers and so, are not enough to solve this problem. Even if the authors of these libraries decide to decouple the functionality of the SerialPort basic wrapper in their design, there is little gain in it, users should still manually extract those files and integrate them in their projects, which doesn’t sound as reasonable engineering and will produce, for sure, maintenance problems and lack of updates. It is really unlikely that the authors will decide to create a separate project/library for the SerialPort, it is more effort not only to do it in the short term, but also to maintain and work with it in the mid and long terms. So developers just roll out their designs, and fill the functionality in it as required. I’ve done it so many times too...

“Effective Modern C++” from Scott Meyers Review -- CoderGears Team

By Blog Staff | Nov 27, 2014 03:54 PM | Tags: None

Today on CoderGrears:

“Effective Modern C++” from Scott Meyers Review

by CoderGears Team

From the article:

This month a new book from Scott Meyers become available, it’s the last one of its Effective software development series (More Effective C++, Effective STL   and Effective C++ ) .

In this book Scott Meyers focus on the new C++11 and C++14 standrads, currently few books talk about them. In the other side many resources are available on the web discussing these new standards. Why I need to read this book?

Here’s our feedback...

The Python API and C++ -- Scott Prager

By Blog Staff | Nov 27, 2014 03:49 PM | Tags: None

Some interspecies dating, appropriately on the "multi-paradigm" blog:

The Python API and C++

by Scott Prager

From the article:

Recently, for a job interview task, I was asked to write a Python module with a C or C++ implementation to solve an otherwise simple task. Obviously, I chose C++. While I had never used the Python API before, I found that the existing information on extending Python with C quite sufficient. What surprised me, however, is how little information existed for using C++. A few libraries exist, like Boost.Python, PyCXX, and some utilities that parse C++ to create Python bindings, but I didn't find much in the way of actual information without examining the sources of these libraries. ...

... I have started working on a little utility library (https://github.com/splinterofchaos/py-cxx) for personal use... [The Python C API has] many restrictions and it certainly puts a cramp on C++'s style, but the moral of this store is that just because you need to work with a C API doesn't mean you can't use modern C++ techniques.

N4340: Remove Deprecated Use of the register Keyword -- Alisdair Meredith

By Blog Staff | Nov 27, 2014 03:46 PM | Tags: None

New WG21 papers are available. If you are not a committee member, please use the comments section below or the std-proposals forum for public discussion.

Document number: N4340

Date: 2014-11-26

Remove Deprecated Use of the register Keyword

by Alisdair Meredith

Excerpt:

The register keyword was deprecated in the 2011 C++ standard, as its effect was already implicit in the language. It remains reserved for future use by the standard, and is time to remove its vestigial specification.

Post-Urbana mailing available

By Blog Staff | Nov 27, 2014 03:40 PM | Tags: None

The post-Urbana mailing of new standards papers is now available.

NOTE: A number of these papers have already been publicized on this blog. This is the complete list including ones not previously publicized.

Free CppCat for Students

By Andrey Karpov | Nov 26, 2014 09:41 PM | Tags: None

CppCat is a static code analyzer integrating into the Visual Studio 2010-2013 environment. The analyzer is designed for regular use and allows detecting a large number of various errors and typos in programs written in C and C++. For the purpose of popularizing it, we've decided to launch a student-support program granting free licenses to every higher school student who will contact and ask us about that. You just need to send us a photo of your student card or transcript.

A few words about static code analysis

Static code analysis tools draw the programmer's attention to those fragments which are very likely to contain errors. Here's a simple example:

double var_z;

....

var_z = ( var_z - 16 / 116 ) / 7.787;

This code is correct from the viewpoint of the language and compiler. It's just a regular situation when division of the integer number 16 by integer number 116 results in 0. Expressions like that are necessary sometimes. However, the analyzer takes a wider perspective of the code and detects an error pattern: if the result of such an integer division is then used together with the double type, it may signal something is wrong.

The analyzer will draw your attention to this suspicious division with the following warning: V636 The '16 / 116' expression was implicitly casted from 'int' type to 'double' type. Consider utilizing an explicit type cast to avoid the loss of a fractional part. An example: double A = (double)(X) / Y;. color.c 125

The code was most likely meant to look as follows:

var_z = ( var_z - 16.0 / 116.0 ) / 7.787;

The division now results in 0,137931 instead of 0.

Static analysis tools can be treated as an extension to compiler warnings. Unlike the compiler, analyzers deal with higher-level constructs and rely on empirical methods trying to guess if the code works the way the programmer wanted it to.

A few words about the CppCat analyzer

CppCat is a static code analyzer which is easy to set and use. It is an excellent tool to get started with the static analysis methodology. It is not as powerful as its big brother PVS-Studio (see their comparison), but it is more than sufficient for most tasks. In any case, CppCat's functionality is surely quite enough for students and single developers.

The analyzer can integrate into Visual Studio 2010, 2012, 2013. Unfortunately, it can't integrate into Express editions and we can't help it as Visual Studio Express editions don't support plugins.

The analyzer supports the following languages: C, C++, C++/CLI, C++/CX.

An important feature of the analyzer is an automated analysis of freshly modified code. After compilation of modified files is finished, CppCat starts analyzing the code in background and displays a warning whenever anything suspicious is found. This feature allows programmers to detect errors at the very early development stage and thus save time on bug search and fixes.

You can download CppCat from the product's website: http://www.cppcat.com

How to get a CppCat license

Using CppCat will help you in acquiring skills of working with static analysis tools and improving your qualification. Static analyzers are growing more and more popular nowadays, so it'll be just good if you can specify in your résumé that you know how to use these tools.

To get a license you just need to send to our email team@cppcat.com a photo or scan of your student card, transcript or other document confirming that you are a higher school student. Please specify your first and second name and the name of your university as it might be very difficult to make out this information from the photo. These data will be used to generate your personal registration key.

The license will be valid through 1 year. If you wish to be able to use CppCat after that, you will have to send us a new photo of your student card.